Dresser masoneilan, a world leader in the field since 1879, manufacturesa range of consolidated safety/safety relief valves. The 1700 2 s series maxiflow safety valve is available in a full range of sizes for sub critical steam up to 3,000 psi and l120°f. It is also available for supercritical steam service applications up to 4,500 psi at l,050°f and 5,360 psi at 750°f. It is asme approved and certified by national board of boiler and pressure vessel inspectors for relieving capacity at 3% overpressure in accordance with asme section ib & pv code. The valve design is also asme approved and capacity certified at 10% overpressure in accordance with asme b&pv code section viii. The unique features of the valve are pressure assisted closing, three separate valve adjustments, thermodisc seat design, spherical bearing surfaces, two adjusting rings, adjustable lift, grooved disc holder, optimum length to diameter guide ratio, adjustable lifting gear, etc. Type 181l safety valve is a high capacity flanged safety valve designed for steam service and available in two pressure classes [300 and 600] and sizes 1 l/4 in to 6 in. Capacities are certified at 3% and 10% overpressure in accordance with section i and section viii. The features include low spindle bearing point and concentric spindle loading, thermodisc seat design, seal welded seat bushing, two adjusting rings, etc. The 1900 series are flat seated, top guided, high capacity valves conforming to api 520, 526 and 527, available in ansi pressure classes 150 lb to 2,500 lb.
